Water Molecule

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Project Name: Water Molecule Penny Test Overview & Background: I am an intern at a Water Resources Institute assisting in the education and outreach program. Objectives: To be able to not just show an image of a water molecule but let them hold and truly understand it. Through the activity we can also teach students about cohesion, adhesion, and surface tension and how they can affect water and your experiments. Audiences: We do this with students from kindergarten to seniors in high school but the final info must be adjusted for age and learning goal. Subjects: Earth Science, Chemistry Skills Learned (Standards): Team work, properties of water, independence on working, and the properties of water Also a working knowledge of cohesion, adhesion, and surface tension. Lesson/Activity: We use this in explaining the special qualities of water. We mainly focus on cohesion, adhesion, and surface tension and allowing them to design their own way to set up an experiment. They are told to figure out how many drops can fit on a penny. In groups of two they must do six trials three on heads and three on tails. Duration: 10-30 minutes Preparation: Explain to them the idea and give in groups of two a small beaker of water, two basic pipettes, six pennies, and a tray for the pennies to sit in. Have them predict which side can fit more (or if they might be the same) and how many drops might fit. Then let them go about figuring the rest on their own some will use on penny or all six, others will break up and have on doing heads and one doing tails. When they start make sure they keeping dropping drops until it spills over and that they stop when it does. Also that they do work together and exchange data. After they finish have them make a conclusion of which side held more (or if they found it to be the same). Discus their differing results and how that could have happened. Then introduce the idea of cohesion, adhesion, and surface tension, explain how this can affect the test they just did. If they are young talk about the difference in drop sizes or pennies. This is where you should use the water molecule and show them what causes water to be unique. Finally have them try to think of a way to take out as many variables as possible to make this test more precise and what else they could do to further the experiment. Rubric & Assessment: Your going to want to make sure they made predictions, wrote down the data an a conclusion, but most of the credit should come from a lab report explaining how they did the test, how cohesion, adhesion, and surface tension may have effected their results, and how they could change the experiment or further the idea. If this is a younger group this could be done in discussion instead. Print Settings Printer Brand: MakerBot Printer: MakerBot Replicator (5th Generation) Rafts: Yes Supports: No Infill: 10% Notes: 2 Walls 215* C